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May 30, 2000
What follows is reproduction of a classic discussion thread from the "old" message board on TONMO.com. Enjoy, and by all means, continue!


One thing we've learnt already regarding giant cephalopods is that there are many wildly inaccurate and exaggerated claims as to how long and heavy some of them are (case in point, Enteroctopus dofleini).

Architeuthis dux has long held the record as the largest cephalopod thus far known, but is it? Many of the claims of 1 ton and 60 foot long specimens I believe are quite unsubstantiated or exaggerated (even those reports of 57 foot long specimens from New Zealand back in the 1880's - which were paced rather than measured). I would have seen 80 of these animals now and the largest specimen I have ever come across was 2.25m mantle length, 12m total length, and weighed 250kg. It was a female, and I believe the female attains considerably larger sizes than the male. I do not expect Architeuthis dux to grow much larger than this (if there really is a single species of Architeuthis world wide, and certainly most of the evidence points to this fact nowadays).

However, there are other very large cephalopods out there, and I would be extremely interested to discuss records of these to determine the true maximum lengths and weights that these animals can attain. I would imagine, in collections around the world, that people are sitting on a goldmine of unpublished material - and that there are many large specimens of the following species that have not been reported in scientific literature. I would be very interested to hear from anyone with such specimens, or information that they could contribute to this discussion.

The species I am particularly interested in are the squids:
Architeuthis dux
Moroteuthis robusta
Moroteuthis robsoni
Moroteuthis ingens
Kondakovia longimanna
Dosidicus gigas
Taningia danae
Mesonychoteuthis hamiltoni
?Magnapinna sp. (the new squid)
Thysanoteuthis rhombus
Idioteuthis cordiformis
Lepidoteuthis grimaldi

And the octopuses:
Haliphron atlanticus
Enteroctopus dofleini

If you have information that you can contribute to this site for any of these species please start up a NEW TOPIC on this message board with that species name as the topic title; collectively (with a little help from people who I hope join up) we'll get to the bottom of maximums in due course. I'll contribute what information I have for them also - almost all of which is unpublished. Should you have additional species that you consider worthy of calling 'giant' please feel free to add and discuss these also.

Initially it would be interesting to compile maximum lengths and weights from web sites, and eventually, if lucky, we'll be able to source these to the original citations (much like we did for Enteroctopus dofleini - I enjoyed that process immensely). I would imagine that we'll end up reducing some reported maximums .... but at the same time I would imagine that we will end up increasing others.

Don't be put off by the Latin, if you're not a cephalopod expert. And don't be afraid to post anything that you're not sure about - it's a learning curve for me too.

I look forward to some lively and active discussion.

If you don't mind considering fossil cephalopods, the Link below shows a giant ammonite

Giant Ammonite

I don't know if the shell is complete, but the animal that lived in it was still a giant.


Re: GIANT CEPHALOPODS|steve_oshea|
Kevin, I don't mind giant fossil cephalopods/ammonites at all; this would be both an exciting and new development - it's an area I know too little about unfortunately.

I would really enjoy some paleontological discussion on this site.
Cheers, Steve

That thing is astounding! Thanks for sharing that link.

Re: GIANT CEPHALOPODS|steve_oshea|
...whatever lived in (or outside ... if the shell is internalised) that shell left Architeuthis for dead in the sinister stakes.

What I'd do to see a live ammonite....

Re: GIANT CEPHALOPODS|mietek_golos|
I consider the following two species worthy of inclusion in the "Giant Cephalopod" list:

Megalocranchia fisheri
- Body: up to 1.8m;
- Distribution: At least off Hawaii;
- Altitudinal distribution: surface to mid- depth waters of open ocean.

Enteroctopus magnificus
- Common Name: Southern Giant Octopus;
- Body: up to 35cm;
- Arms: up to (at least) 1.5m;
- Distribution: Southern Africa (from Namibia to Port Elizabeth, South Africa;
- Altitudinal distribution: cool waters from shallow subtidal areas to 1,000m deep.


Hope the information helps a bit,
Mietek Golos.


I think we should build a time machine and go back to when the ammonites ruled the sea and to see herds of trilobites (maybe not herds?) because we only get to see very few of the animals that lived back then.

Or if you aren't too sure about time travel you could just stat beleiving in reincarnation and come back as a giant squid right?! i think that would be pretty cool:)

Re: GIANT CEPHALOPODS|steve_oshea|
Thanks for those Michael and Serena (I think Tony should build a time machine online ....). Michael, I'll look into both species and post shortly; just been a tad busy this past week.
Cheers, O

More giant fossil cephs


See F. Cephalopods (Teuthids) near bottom of page

? do extant squid (like architeuthis) have pens ?

Re: GIANT CEPHALOPODS|tintenfisch|
Yes, extant squid have pens (also called the gladius).

Thanks Tintenfisch.
I was also wondering if gladii are commonly found washed up on beaches, or laying on the sea floor (especially after semelparous activity), or do they decay rapidly?

Re: GIANT CEPHALOPODS|steve_oshea|
Good question Kevin. I'll have a stab at that one. When processing soft-sediment core samples, most of my experience being with deep-sea cores (~1000-3000 metres off New Zealand), you very often find large numbers of squid and octopus beaks and hooks, but I do not recall ever having seen even fragments of the gladius or of sucker rings; sometimes you find large numbers of hatched cirrate egg capsules too (these 'dumbo' octopus eggs). I'd never even thought of it until your post.

I guess the pen/gladius breaks down quite rapidly, as must the sucker ring, compared to that of the beak or hook. A difference in their composition could be behind their different relative rates of decay; I'll do some digging.

Kevin, if you are interested in fossil squids, here is a link to a photo of an 80 million year old pen of a fossil giant squid of the Cretaceous period. It measures 92cm long and was found in Manitoba.


I originally posted this under the heading 'Tusoteuthis' so apologies if you have already seen it.

Thanks Steve and Phil,
Looks like most of the hard parts of squid are to be found in deep, or low energy environments. I guess that rules out finding squid parts here in Utah, we have mostly shallow, high energy, nearshore deposits, at least in the Cretaceous. We do have a squid gladius reported from the Permian (very small) I guess I will look there, it is in a phosphatic upwelling deposit. Maybe I can find a giant Permian Squid!

Re: GIANT CEPHALOPODS|steve_oshea|
I wouldn't rule out finding squid bits in Utah (I'm just more familiar with deeper-water deposits, simply because that's the sort of environment I work on); low-energy environments sure would be the place to start looking, whether shallow or deep.

Evidently, not far from where I'm to move to next year (Feb; new job), there are deposits wherein squid hooks (and possibly 'other bits') have been found (I can't remember the specifics, as in age of the deposits - had this discussion with someone many years ago now); might have to go on a jaunt and do a little more digging. There's belemnites and ammonites in 'them there' hills too. Best get myself one of those fandangled GPS things so as I don't get lost (might have to get a 4 wheel drive too, with bullbars [read 'treebars'], just in case Tintenfisch tags along!).
Cheers, O

Re: GIANT CEPHALOPODS|tintenfisch|
... and possibly a car with a standard transmisison, so when it stalls it's at least partly justifiable. ;)

I've been looking at the gladii from Nototodarus, (measuring the growth increment lengths....whose stupid idea was that!!!) and they are incredibly fragile when they're dry, look sideways at them and they crumble, so it's no wonder they don't survive often in the fossil record (I've also had a look at some Moroteuthis ingens ones and they're just as fragile) I even tried storing them in alcohol but they delaminated! Any I've found in gut contents have been in very small pieces, I looked in squid, fur seal, penguin, albatross and a variety of finfish guts, scats and regurgitates and the gladii are all macerated (on second thpoughts measuring isn't so bad!!)


Re: GIANT CEPHALOPODS|steve_oshea|
Interesting observation that Jean, re the delamination in alcohol (I've not heard of this before, and have not experienced it myself). Because of the cost of ethanol (ETOH) in New Zealand (prohibitively expensive), as opposed to isopropyl alcohol, I use the latter. Because ETOH is used at the higher concentration of 70-80%, whereas isopropyl is used at the lower 40%, I'm wondering whether the higher alcohol concentrations have something to do with the delamination. Was it ETOH that you were using?

I find ETOH to be less desireable for storing cephalopods in (as a preservative; as opposed to the 5-10% formalin solution to fix them in), as it dessicates the tissues, makes the animals that much harder and sends their anatomy rather opaque. The gladii I have here, many taxa, are all in the 40% isopropyl preservative, and not one shows any trace (at a macro level) of delamination. Perhaps you should try this (I've also fixed them in formalin soln. initially, which might affect them).

All that aside, how goes the writing down there in sunny Otago? You must be close to submission now.
Cheers, O

Hiya Steve,

yes I was using 70% ETOH and that may have had a bearing on the delamination effect. All of mine are now stored dry in spaghetti jars!! But I'll keep the isopropyl alcohol in the back of my mind for next time!

As for submitting, all I'll admit to is before christmas! And its very sunny down here at the moment, which makes the writing that much harder!


Re: GIANT CEPHALOPODS|steve_oshea|
Sounds interesting; I'd make sure you have at least sprayed them with a 5% formalin soln (to stop any fungal attack). One alternative would be to immerse them in a 5% formalin/baby oil solution, then leave them to dry somewhere (tissue dry to begin with to soak up the excess); this should keep them quite soft/flexible (an old chiton preserving mix I used to use - chiton as in Polyplacophora, not as in chitin).
Cheers, O

By 5% formalin/baby oil, do you mean 5%formalin & 95% baby oil? Is that appropriate for moroteuthis robusta beak/gladius/radula? We've recently dissected one and would love to preserve those parts.

It's because, saddled with the name of "giant gelatinous octopus", it feels rather shy and hides for fear of ridicule. :mrgreen: I mean, if you were a giant gelatinous blob of an octopus, you'd probably feel sad that the cool cephs, like colossal squid and vampyroteuthii, get all the babes, wouldn't you?

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